The present invention provides a novel method for producing carboxymethylated cellulose, the method making it possible to economically obtain a high-transparency cellulose nanofiber dispersion. In the carboxymethylation of cellulose, mercerization is carried out in a solvent comprising mainly water, and then carboxymethylation is carried out in a mixed solvent of water and an organic solvent. A nanofiber dispersion of high-transparency carboxymethylated cellulose can be obtained by defibrating the resulting carboxymethylated cellulose.

A method for fiber modification provided in the present disclosure comprises steps: fibers react with a hypochlorous acid oxidant for development of antioxidant fibers, separate the antioxidant fibers from the hypochlorous acid oxidant and dry the antioxidant fibers for development of modified fibers which feature better oxidation resistance.

A method for fiber modification provided in the present disclosure comprises the following steps: reacting fibers with a hypochlorous acid oxidant for development of antioxidant fibers, separating the antioxidant fibers from the hypochlorous acid oxidant and drying the antioxidant fibers to develop modified fibers which feature better oxidation resistance.

A stainable decorative sheet having good adhesion between a paper base material and a nonwoven fabric with a surface excellent in tactile sensation and stainability, excellent transparency, and a method for coloring the stainable decorative sheet. The stainable decorative sheet includes a paper base material, an adhesive layer, a nonwoven fabric layer, and a transparency improving layer in a predetermined structure, wherein the nonwoven fabric layer partially has a filling part A and a filling part B in a part of voids among fibers of the nonwoven fabric layer.

Disclosed are fibers which contain identification fibers. The identification fibers can comprise one or more chemical markers, or taggants, which may vary among the fibers or be incorporated throughout all of the fibers. The disclosure also relates to the method for making and characterizing the fibers. Characterization of the fibers can include identifying chemical markers and correlating the chemical markers and a taggant chemical marker amounts of at least one of the chemical markers to manufacturer-specific taggants to determine supply chain information. The supply chain information can be used to track the fibers from manufacturing through intermediaries, conversion to final product, and/or the consumer.

A description is given of continuous fibers based on cellulose and/or cellulose derivatives, more particularly for producing flame-retardant textiles or carbon fibers. The cellulose and/or the cellulose derivatives are in a dehydrated form in the continuous fibers. The oxygen content is 29 to 39 wt %, the limiting oxygen index LOI is 25 to 40 (according to DIN EN ISO 6941; 2004-05) and the density is 1.3 to 1.45 g/cm.sup.3 (according to DIN 65569-1; 1992-10). The continuous fibers may be produced advantageously by impregnating the starting fibers with a solution, more particularly an aqueous solution, of a specific salt which under thermal conditions releases a dehydrating acid which brings about the dehydration of cellulose and/or of cellulose derivatives in a subsequent thermal stage. The continuous fibers of the invention can be used in particular to produce advantageous carbon fibers.

The invention relates to a process for preparing a polysaccharide derivative, comprising the steps of: (a) contacting at least one polysaccharide with at least one polysaccharide swelling agent at a temperature of at most 70° C.; and (b) subsequently, contacting the product of step (a) with at least one aromatic isocyanate; thereby preparing a polysaccharide derivative.

Provided is a novel manufacturing method whereby a carboxymethylated cellulose nanofiber dispersion having high tarnasparency can be obtained economically. In carboxymethylation of cellulose in the present invention, mercerization is performed in water as the main solvent, after which carboxymethylation is performed in a solvent mixture of water and an organic solvent, By defibrating the resultant carboxymethylated cellulose, a carboxymethylated cellulose nanofiber dispersion having high transparency can be obtained economically.

A carboxymethylated cellulose having a carboxymethyl substitution of no more than 0.50 and a cellulose I type crystallization of at least 50%. Ideally, the anionization is 0.00-1.00 meq/g. The Schopper-Riegler freeness is ideally at least 60.0° SR. Ideally the ratio of filtration residue is 0%-30% by mass. The viscosity (30 rpm, 25° C.) for an aqueous dispersion having a 1% solid content (w/v) is ideally no more than 10.0 mPa.Math.s.

Disclosed are fibers which contain identification fibers. The identification fibers can comprise one or more chemical markers, or taggants, which may vary among the fibers or be incorporated throughout all of the fibers. The disclosure also relates to the method for making and characterizing the fibers. Characterization of the fibers can include identifying chemical markers and correlating the chemical markers and a taggant chemical marker amounts of at least one of the chemical markers to manufacturer-specific taggants to determine supply chain information. The supply chain information can be used to track the fibers from manufacturing through intermediaries, conversion to final product, and/or the consumer.